Various types of machines are used for moving earth and other types of work. Such machines typically have an attached implement such as a bucket, a blade or other implements used for material handling. Typically, such machines may be configured to perform various work cycles. For example, a track type loader or a wheel type loader typically has a bucket which may be configured to perform a work cycle that includes digging, collecting (racking) a load, carrying a load, and/or dumping a load. Generally, such machines have a frame and the implement is connected to the frame by a linkage. As the machine performs a work cycle, various portions of the implement and linkage may be operated as the machine is propelled across the ground. Most of these functions apply a load on the engine, thereby increasing the heat generated by the engine.
Internal combustion engines and associated cooling systems, particularly the fan associated with such cooling systems, tend to be relatively noisy. Governmental bodies in many countries are continuously striving to require engine and vehicle manufacturers to reduce the noise output of their products. Manufacturers also desire to reduce the noise level in order to provide operators and bystanders with a more comfortable atmosphere. One step in reducing noise is to provide separate enclosures for the engine and the cooling system.
Additional noise reduction of engine cooling air systems can be achieved by insulating the area of the cooling system enclosure near the fan and radiator with a sound absorbing material, including the use of a “sound wall” disposed between the cooling system and engine enclosures. When the fan is operating, it draws ambient air into the cooling system enclosure and across the radiator and creates a pressure drop across the cooling system enclosure. Without the sound wall, hot air from the engine enclosure would be free to pass across the radiator in competition with the ambient air being drawn into the cooling system enclosure by the fan, which would reduce the efficiency of the cooling system. Thus, in addition to sound insulation, the sound wall may also be designed to limit or prevent hot air from the engine enclosure from passing across the radiator.
However, there is often a need to pass cooling air or exhaust air between the engine and cooling system enclosures and through the sound wall via air ducts. For example, the air ducts may be part of an input or an output to the turbocharger system of the engine. When the fan is operating, the pressure drop across the cooling system enclosure caused by the fan can cause the sound wall to move, which permits hot air from the engine enclosure to pass through the openings in the sound wall that accommodate the air ducts. As a result, a seal is needed between the sound wall and the air ducts because it is undesirable to permit hot air from the engine enclosure to be drawn across the radiator as opposed to ambient air being drawn across the radiator by the fan. While sound walls with grommets through which the air ducts pass are known, currently available grommets can lose contact with the sound wall if the sound wall moves or flexes. As a result, hot air from the engine enclosure can still be drawn across the radiator, which reduces the efficiency of the cooling system.
Accordingly, there is a need for a seal between the air ducts and the sound wall which permits the sound wall to flex or move without permitting air from the engine enclosure to pass through the sound wall and across the radiator, which would adversely impact the efficiency of the cooling system.